Daughter is heading to Europe for a year - studying in Germany for 6 months then working in France. For phone is the best option to run a dual sim - buying a payg when she gets to Germany - and cloning WhatsApp to have a local one while keeping her UK number? Maybe there is a way to set the UK sim to WiFi only?
Android Dual SIM phones should allow you to chose what is on / off for each use case. You can disable mobile data for one for example, but all apps will work using WiFi. I would imagine that Apple so something similar, just more expensively.
Daughter is heading to Europe for a year - studying in Germany for 6 months then working in France. For phone is the best option to run a dual sim - buying a payg when she gets to Germany - and cloning WhatsApp to have a local one while keeping her UK number? Maybe there is a way to set the UK sim to WiFi only?